Method of applying a getter to vacuum devices



April 26, 1927.

o. s. Gus'rm METHOD OF APPLYING A GETTER TO VACUUM DEVICES Filed Sept; 12, 1922 .FIGLI- T Y R5 W mu R G O E n M A Patented Apr; 26,1927.

UNITED STATES 1,626,235 PATENT OFFICE.

DANIEL SNYDER GUS'I'IN, OF NEWARK, NEW JERSEY, ASSIGNOR T WESTINGHOUSE LAMP COMPANY, A CORPORATION 01 PENNSYLVANIA. 7

METHOD OF APPLYING A GETlI-E'B TO VACUUM DEVICES.

Application filed September 12, 1922. Serial No. 587,654. I

This invention relates to a method of applying a getter or clean-up agent to electrical devices and more particularly to the application of a getter or clean-up agent to a as-filled, incandescent electric lamp.

n object of my invention is to simplify the methodof applying a getter to a lamp. Another object is to provide amethod for applying a getter to a lamp part in such manner as to obtain the maximum efiiciency of the getter. Y

A further object is to apply a getter in such manner as to be able to activate it to effect a quick clean-up action upon deleterious gases in all parts of a lamp.

A still further object 'is to provide a.

' method whereby a getter may be applied to a gas-filled lamp without the use of a binder or other vehicle. 7

Other objects will be apparent from a reading of the following specification.

'In certain types of electrical devices, particularlydncandescent electric lamps of the gas-filled type, it is desirable to provide a 'material which, upon activation, will cleanup any residual gas that may have been left in the bulb after evacuation, or-of occluded gases which may be given off, if the bulb of the lamp has been given what is termed'a cold exhaust. A material of the above charactor is known in the art as a clean-up agent.

In lamps of the gas-filled type, it has been found undesirable to use a getter or clean-up agent which is carried in a binder or other vehicle. It has been found that, by the use of getters as heretofore used, the decomposition of the 1 binder releases certain carbonaceous substances that have a detrimental effect u on the life of the lamp.

for the application of a getter in its pure state and it has been found that, by utilizing the adherent property of the getter'material to the mount. the-desired results are obtained without the use of any binder or other foreign substance for carrying the get ten It has been common to apply getters to such portion of the inner structure of a lamp or other device as will subject the getter to sufiicient heat to vaporize at: Various methods of applying getters have been employed; for instance, the bead or similar mass of getter material has been deposited on the mount, or the mount may have been dipped in'a solution in. which the getter ma- 'it is believed that too much discoloration within the lamp would result. since, when a mass of getter material is decomposed, it gives a sputtering action or melts gradually. This is particularly true where the heat is not intense enough to provide for the efficient vaporization of the material of the mass.

In the present invention, a getter material is applied in the powdered. state, and any sultable portion of the interior of the lamp may be dipped, in, or otherwise coated with, the pure getter substance, particularly aluminum powder, which has been found to cling to certain portions of a lamp as, formstance, the filament or parts of the mount, and a getter so disposed may be subsequently activated when the lamp is lighted.

It has been found preferable to dip a mount into a receptacle containin powder of any substance that will give 1: e getter action. Aluminum powder has, however,

been found to give good' results when em ployed in'pra'cticing my method. By dipping the mount into the powdered material, the powder becomes well distributed over a given area of the filament and, when activated, serves'to clean-up the entire atmosphere within the bulb. This manner of distributing the getter material also provides for the rapid action of the getter since it is obvious that, with the thin layer applied by dipping, the filament may' be heated to a considerably less degree than is necessary when a comparatively large amount of getter material is used in a eon- 10o centrated mass.

Considerable advantage is, therefore, derived from the fact that the getter may be activated with a filament of relatively low temperature since there will be less 106 alteration in the filamentary structure. The vaporization of getters which require the heating of a filament to a relatively hi h temperature tends to make the filament'brit- 'tle, and a lamp gettered by my method will 110 have a filament more tenacious and, therefore, more readily ada ted for general han dling and transportation, which is a practical advanta e in lamp manufacture. j

The 51117811131011 will be more clearly under stood by reference to the accompanfyihg drawing which shows an a plicationo my invention to an electrical. evice, one of the standard gas-filled lampsbeing shown as an example.

Fig. 1 is a view, in elevation, of a mount during the dipping operation;

Fig. 2 shows a mount in a holder and a bulb positioned in a given relation thereto, jaws for holding the bulb and a holder for the exhaust tube being indicated-in dotted lines; and, a

Fig. 3'shows a finished: lamp of the gasfilled type. v In theembodiment of the invention shown, the mount may consist'of the usual stem having an arbor 5, flaretube 6 and exhaust tube 7," as well as the leading-in wires 8, which "are sealed into the 9 of the stemin the usual manner.

The mount, as'shown, isprovided wlth a ring-type filament 11 carried on support wires 12. The mount may-bedipped-"lntoabpowdered getter 13 contained m a suitrece tacle. l4, and dipped mounts may be place incorporation with a bulb and other lamp 'i li' t Y 1 ti 0 get ermg em on he readil as' provided by my method, may

combined as a step in the manufacture o lamps. It will be understood, that lamp mounts are sealed into bulbs 'by certain lamp-making machines which. are well'known 1n the art.- When ofie'r'atingsuch machines, the operator usua y icks up a mount, places it in a holder 16 oi a machine in a given position and gpsitions' the bulb between jaws 17, as in- 'cated in dotted lines,"over the mount. The machines then operate to heat certain por-.

tions of the-mount and the J bulb, whereupon other mechanical elements are actuated to effect a bulb.-

union of the mount to the During this operation, which is known as the sealing-in operation, an o rator may,

without any appreciable loss 0 time, dip a mount mto a powdered material prior to in a rack preparatory to their flipped portions of the mount. The operator may quickly dip the mount, shake off any excess material and then .insert the mount into the sealing-in machine.

The amount of getter material applied to a mount may be governed by the size of the particles of the powder or b the extent to which the mount is dippe intothe powder. Various expedients 'have heretofore been tried for efliciently getterin lamps of the gas-filled type but, owmg to t e supposed need of a hinder" or other'vehicle for carrying the getter material efiicient results have not been obtained. l3

however, I have avoided-the necessity getter and am able to use a gettering substance, suchas aluminum, to, reduce the desired high vacuum. The pro notion of a high vacuum by the vaporization of the aluminum seems to indicate that a reaction occurs directly with any oxygen and, I

because the aluminum is' distilled off and has no protect film of oxide, it is. in a state to react d1rectl with water to form the hydroxide which is, in iteself, a good dehydrating agent.

Although I have described what, at thepresenttime, may be considered a preferred embodiment of m with other devices and ferent characters.

What is claimed is:

1.' The method of applying powdered clean-up-agent material to a vacuum device which comprises di ping a, portion of the of the mount in the sealin or this purpose, a receptac e asy my 'methodf,

o using any other material for carrying the 75 invention, it is to be 1 understood that t e method. is utilizablei 00 with. getters of dif- I internal structure 0 said device into such whlc comprises mount mtomy name this 11th day; of 'Sep-' 

